This invention relates to a method for treating coffee beans to make a better-tasting coffee. The invention also relates to an improved roast and ground coffee product.
In the typical process for making roast and ground coffee, the coffee beans are cleaned, then blended, and then roasted at temperatures between about 350.degree. F. and 550.degree. F. for times between about 1 minute and 25 minutes, depending on the roaster and the desired degree of roast. The roasted beans are then ground and normalized to produce the roast and ground coffee product. Soluble coffee is generally made by countercurrently extracting roast and ground coffee, concentrating the extract, and then drying the extract. Unfortunately, coffee prepared according to these typical methods can have some harsh, bitter, or undesirable tastes.
A number of methods have been used for treating coffee beans to improve the taste or otherwise affect the coffee. For example, in U.S. Pat. No. 2,119,329 to Heuser, issued May 31, 1938, Heuser states that coffee having a richer flavor can be prepared by adding a small amount of oxidizing agent to the green coffee beans. About 0.25% by weight of the coffee of sodium hypochlorite can be added, usually by spraying the beans with an aqueous solution of the hypochlorite.
U.S. Pat. No. 1,640,648 to Cross, issued Aug. 30, 1927, discloses a process for decaffeination in which green coffee beans are first treated by an alkaline agent to convert the caffeine to an alkaloidal state, and the beans are subsequently roasted and decaffeinated in a single step.
In U.S. Pat. No. 312,516 to Schilling, issued Feb. 17, 1885, Schilling states that the full flavor and strength of coffee is brought out by coating the roasted beans with an alkaline salt, for instance bicarbonate of soda or borax. The alkaline salt is dissolved in water and sprayed onto beans still hot from roasting. The beans are subsequently ground.
U.S. Pat. No. 1,822,227 to Lendrich, et al., issued Sept. 8, 1931, discloses a process for making a better tasting coffee by decomposing the chlorogenic acid in coffee beans. The process involves treating green coffee beans with a heated solution of sodium hydroxide, potassium hydroxide, and mineral acid. The beans are subsequently neutralized before roasting.
Lastly, U.S. Pat. No. 3,644,122 to Yeransian, issued Feb. 22, 1972, discloses a process in which ground, roasted coffee or spent coffee grounds are treated with an alkaline material to provide coffee extract said to have increased yield and improved color.
It is an object of the present invention to provide a process for making a better-tasting coffee, in particular a coffee having a richer taste.
It is also an object of the present invention to interfere with the roasting reactions in a manner that results in a better-tasting coffee.
It is another object of the present invention to make the better-tasting coffee by altering the final chemistry of the coffee.
It is a further object of the present invention to make a roast and ground coffee product wherein the concentration of undesirable flavors is reduced while the concentration of good coffee flavors is retained and/or enhanced, resulting in a richer-tasting coffee.
It is another object of the present invention to make a roast and ground coffee product having a better aroma, in particular one containing less unpleasant aroma.
These and other objects of the present invention will become evident from the disclosure herein.
All percentages are by weight unless otherwise defined.